Applications3,5-bis(trifluoromethyl)pheny1- magnesium iodide was prepared from 1-iodo-3,5- bis(trifluoromethyl)benzene. Monodeprotected masked hexayne was not particularly stable and hence was used directly without purification in a Sonogashira coupling with 1-iodo-3,5-bis(trifluoromethyl)benzene to provide mono-aryl-end-capped masked hexayne.